Production Operation Management Junaid Zamir SP06-BB-0010 Chapter 1 – Operations and Productivity 2 What Is Operations Management? Production is the creation of goods and services Operations management (OM) is the set of activities that creates value in the form of goods and services by transforming inputs into outputs Organizing to Produce Goods and Services Essential functions: Marketing – generates demand Production/operations – creates the product Finance/accounting – tracks how well the organization is doing, pays bills, collects the money 4 Why Study OM? OM is one of three major functions (marketing, finance, and operations) of any organization We want (and need) to know how goods and services are produced We want to understand what operations managers do OM is such a costly part of an organization 5 What does it covers Basic Management Functions Planning Organizing Staffing Leading Controlling areas it covers Design of goods and services What good or service should we offer? How should we design our products and services? Managing quality How do we define quality? Who is responsible for quality? 7 areas it covers Process design What process will the product require? What equipment and technology is necessary for these processes? Location strategy Where should we put the facility? On what criteria should we base the location decision? 8 areas it covers Layout strategy How should we arrange the facility? How large must the facility be to meet our plan? Human resources and job design How do we provide a reasonable work environment? How much can we expect our employees to produce? 9 areas it covers Supply chain management Should we make or buy this component? Who are our suppliers and who can integrate into our e-commerce program? Inventory, material requirements planning, and JIT How much inventory of each item should we have? When do we re-order? 10 New Trends in OM Global focus Just-in-time performance Supply chain partnering Rapid product development Mass customization Empowered employees Environmentally sensitive production 11 Productivity Challenge Productivity is the ratio of outputs (goods and services) divided by the inputs (resources such as labor and capital) 12 Measurement Problems Quality may change while the quantity of inputs and outputs remains constant External elements may cause an increase or decrease in productivity 13 Productivity Variables Labor - contributes 10% of the annual increase Capital - contributes about 38% of the annual increase Management - contributes about 52% of the annual increase 14 Chapter 4 – Forecasting 15 What is Forecasting? Its is the art and science of predicting a future events. It uses historical data to predict future. It deals in areas of Production Inventory Personnel's 16 Forecasting Time Horizons Short-range forecast Generally for less than 3 months Used for planning purchases, job scheduling Medium-range forecast For 3 months to 3 years Sales and production planning, budgeting Long-range forecast 3+ years New product planning, research and development 17 Distinguishing Differences Medium/long range forecasts deal with more comprehensive issues and support management decisions regarding planning and products, plants and processes Short-term forecasts tend to be more accurate than longer-term forecasts 18 Product Life Cycle Introduction Product design and development critical Frequent product and process design changes Process modifications High production costs Limited models Growth Forecasting critical Product and process reliability Competitive product improvements and options Increase ability Maturity Decline Standardization minor changes Increasing stability of process Product improvement and cost cutting Little product differentiation Cost minimization commonality Research & development 19 Types of Forecasts Economic forecasts Address business cycle – inflation rate, money supply, housing starts, etc. Technological forecasts Predict rate of technological progress Impacts development of new products Demand forecasts Predict sales of existing products and services 20 Forecasting Approaches Qualitative Methods Used when situation is vague and little data exist New products New technology Involves intuition, experience e.g., forecasting sales on Internet 21 Forecasting Approaches Quantitative Methods Used when situation is ‘stable’ and historical data exist Existing products Current technology Involves mathematical techniques e.g., forecasting sales of color televisions 22 Qualitative Approaches Delphi method Panel of experts make forecasts Sales force composite Forecasting technique based on salespersons estimates of expected sales. Consumer Market Survey Input from potential customers 23 Quantitative Approaches Naive approach Assumes demand in next period is the same as demand in most recent period Moving averages It is a series of airthmatic means used to monitor little or no trend Weighted moving average Used when trend is present 24 Exponential Smoothing Form of weighted moving average Weights decline exponentially Most recent data weighted most Requires smoothing constant (α) Ranges from 0 to 1 Subjectively chosen Involves little record keeping of past data 25 Exponential Smoothing New forecast = Last period’s forecast + a (Last period’s actual demand – Last period’s forecast) Ft = Ft – 1 + a(At – 1 - Ft – 1) where Ft = new forecast Ft – 1 = previous forecast a = smoothing (or weighting) constant (0 ≤ a ≤ 1) 26 Time Series Forecasting Forecasting obtained by observing response variable at regular time periods 27 Trend Component Persistent, overall upward or downward pattern Changes due to population, technology, age, culture, etc. Typically several years duration 28 Seasonal Component Regular pattern of up and down fluctuations Due to weather, customs, etc. Occurs within a single year 29 Cyclical Component Repeating up and down movements Affected by business cycle, political, and economic factors Multiple years duration Often causal or associative relationships 0 5 10 15 20 30 Random Component Unsystematic, fluctuations Due to random variation or unforeseen events Short duration and nonrepeating M T W T F 31 Chapter 5 – Design of Goods and Services 32 Product Decision The good or service the organization provides society Top organizations typically focus on core products Customers buy satisfaction, not just a physical good or particular service Fundamental to an organization's strategy with implications throughout the operations function 33 Product Strategy Options Differentiation Shouldice Hospital Low cost Mobile Phones Rapid response Wal-mart 34 Product Life Cycle Introduction Product design and development critical Frequent product and process design changes Process modifications High production costs Limited models Growth Forecasting critical Product and process reliability Competitive product improvements and options Increase ability Maturity Decline Standardization minor changes Increasing stability of process Product improvement and cost cutting Little product differentiation Cost minimization commonality Research & development 35 New Product Opportunities 1. Understanding the customer 2. Technological change 3. Political/legal change 4. Market practice, professional standards, suppliers, distributors 5. Developing new products faster can result in a competitive advantage 36 Quality Function Deployment Identify customer wants Identify how the good/service will satisfy customer wants Relate customer wants to product hows Evaluate competing products Compare performance to desirable technical attributes 37 Manufacturability and Value Engineering Benefits: Reduced complexity of products Additional standardization of products Improved functional aspects of product Improved job design and job safety Improved maintainability (serviceability) of the product Robust design 38 Issues for Product Development Robust design Modular design Computer-aided design (CAD) Computer-aided manufacturing (CAM) Virtual reality technology Value analysis Environmentally friendly design 39 Defining The Product First definition is in terms of functions specifications are developed during the design phase Manufactured products will have an engineering drawing Bill of material (BOM) lists the components of a product 40 Product Documents Engineering drawing Shows dimensions Bill of Material Lists components, quantities and where used Shows product structure 41 Service Design Service typically includes direct interaction with the customer Increased opportunity for customization Reduced productivity Cost and quality are still determined at the design stage Delay customization Modularization Reduce customer interaction, often through automation 42 Chapter 6 – Managing Quality 43 Defining Quality The totality of features and characteristics of a product or service that bears on its ability to satisfy stated or implied needs American Society for Quality 44 Quality and Strategy Managing quality supports differentiation, low cost, and response strategies Quality helps firms increase sales and reduce costs Building a quality organization is a demanding task 45 The Flow of Activities Organizational Practices Leadership, Mission statement, Effective operating procedures, Staff support, Training Yields: What is important and what is to be accomplished Quality Principles Customer focus, Continuous improvement, Benchmarking, Just-in-time, Tools of TQM Yields: How to do what is important and to be accomplished Employee Fulfillment Empowerment, Organizational commitment Yields: Employee attitudes that can accomplish what is important Customer Satisfaction Winning orders, Repeat customers Yields: An effective organization with a competitive advantage 46 Different Views User-based – better performance, more features Manufacturing-based – conformance to standards, making it right the first time Product-based – specific and measurable attributes of the product 47 Implications of Quality Company reputation Perception of new products Employment practices Supplier relations Product liability Reduce risk Global implications Improved ability to compete 48 Key Dimensions of Quality Performance Features Reliability Conformance Durability Serviceability Aesthetics Perceived quality Value 49 Costs of Quality Prevention costs - reducing the potential for defects Appraisal costs - evaluating products, parts, and services Internal failure - producing defective parts or service before delivery External costs - defects discovered after delivery 50 TQM Total Quality is a description of the culture, attitude and organization of a company that strives to provide customers with products and services that satisfy their needs. It covers entire organization, from supplier to customer Requires commitment by managements toward excellence in all aspects of products and services that are important to the customer 51 Seven Concepts of TQM Continuous improvement Six Sigma Employee empowerment Benchmarking Just-in-time (JIT) Taguchi concepts Knowledge of TQM tools 52 Continuous Improvement Represents continual improvement of all processes Involves all operations and work centers including suppliers and customers People, Equipment, Materials, Procedures 53 Six Sigma Two meanings Statistical definition of a process that is 99.9997% capable, 3.4 defects per million opportunities (DPMO) A program designed to reduce defects, lower costs, and improve customer satisfaction 54 Employee Empowerment Getting employees involved in product and process improvements Techniques Build communication networks that include employees Develop open, supportive supervisors Move responsibility to employees 55 Quality Circles Group of employees who meet regularly to solve problems Trained in planning, problem solving, and statistical methods Very effective when done properly 56 Benchmarking Determine what to benchmark Form a benchmark team Identify benchmarking partners Collect and analyze benchmarking information Take action to match or exceed the benchmark 57 Just-in-Time (JIT) Relationship to quality: JIT cuts the cost of quality JIT improves quality Better quality means less inventory and better, easier-to-employ JIT system 58 Taguchi Concepts Engineering and experimental design methods to improve product and process design 59 Tools of TQM Tools for Generating Ideas Check sheets Scatter diagrams Cause-and-effect diagrams Tools to Organize the Data Pareto charts Flowcharts Tools for Identifying Problems Histogram Statistical process control chart 60 Inspection Involves examining items to see if an item is good or defective Detect a defective product Does not correct deficiencies in process or product It is expensive Issues When to inspect Where in process to inspect It is necessary for both services and good industry. 61 Chapter 11 – Supply Chain Management 62 The Supply Chain Supply chain management is the integration of the activities that procure materials and services, transform them into intermediate goods and the final product, and deliver them to customers 63 Supply Chain Management 1. Transportation vendors 2. Credit and cash transfers 3. Suppliers 4. Distributors 5. Accounts payable and receivable 6. Warehousing and inventory 7. Order fulfillment 8. Sharing customer, forecasting, and production information 64 Make-or-Buy Decisions Reasons for Making 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Maintain core competence Lower production cost Unsuitable suppliers Assure adequate supply (quantity or delivery) Utilize surplus labor or facilities Obtain desired quality Remove supplier collusion Obtain unique item that would entail a prohibitive commitment for a supplier Protect personnel from a layoff Protect proprietary design or quality Increase or maintain size of company 65 Make-or-Buy Decisions Reasons for Buying 1. Frees management to deal with its core competence 2. Lower acquisition cost 3. Preserve supplier commitment 4. Obtain technical or management ability 5. Inadequate capacity 6. Reduce inventory costs 7. Ensure alternative sources 8. Inadequate managerial or technical resources 9. Reciprocity 10. Item is protected by a patent or trade secret 66 Outsourcing Transfers traditional internal activities and resources of a firm to outside vendors Firms outsource information technology, accounting, legal, logistics, and production 67 Supply Chain Strategies Negotiating with many suppliers Long-term partnering with few suppliers Virtual companies that use suppliers on an as needed basis 68 Vertical Integration Vertical Integration Raw material (suppliers) Backward integration Current transformation Forward integration Examples of Vertical Integration Iron ore Silicon Farming Automobiles Integrated circuits Flour milling Distribution systems Circuit boards Dealers Computers Watches Calculators Steel Finished goods (customers) Baked goods Figure 11.2 69 Virtual Companies Rely on a variety of supplier relationships to provide services on demand Fluid organizational boundaries that allow the creation of unique enterprises to meet changing market demands Exceptionally lean performance, low capital investment, flexibility, and speed 70 Vendor Selection Vendor evaluation Find potential vendors Determine the likelihood of them becoming good suppliers Vendor Development Training Engineering and production help Establish policies and procedures 71 Vendor Selection Negotiations Cost-Based Price Model - supplier opens books to purchaser Market-Based Price Model - price based on published, auction, or indexed price Competitive Bidding - used for infrequent purchases but may make establishing long-term relationships difficult 72 Distribution Systems Trucking Moves the vast majority of manufactured goods Railroads Capable of carrying large loads Airfreight Fast and flexible for light loads May be expensive Waterways Typically used for bulky, low-value cargo 73 Distribution Systems Pipelines Used for transporting oil, gas, and other chemical products 74 Chapter 12 – Inventory Management 75 Inventory One of the most expensive assets of many companies representing as much as 50% of total invested capital Operations managers must balance inventory investment and customer service 76 Functions of Inventory 1. To separate various parts of the production process 2. To save firm from fluctuations in demand and provide a stock of goods that will provide a selection for customers 3. To take advantage of quantity discounts 4. To hedge against inflation 77 Types of Inventory Raw material Purchased but not processed Work-in-process Undergone some change but not completed A function of cycle time for a product Maintenance/repair/operating (MRO) Necessary to keep machinery and processes productive Finished goods Completed product awaiting shipment 78 ABC Analysis ABC analysis is a business term used to define an inventory categorization technique often used in material management. Analysis of a range of items which have different levels of significance and should be handled or controlled differently. 79 ABC Analysis When carrying out an ABC analysis, inventory items are valued with the results then ranked. "A class" inventory will typically contain items that account for 80% of total value, or 20% of total items. "B class" inventory will have around 15% of total value, or 30% of total items. "C class" inventory will account for the remaining 5%, or 50% of total items. 80 Record Accuracy Accurate records are a critical ingredient in production and inventory systems Allows organization to focus on what is needed Necessary to make precise decisions about ordering, scheduling, and shipping Incoming and outgoing record keeping must be accurate Stockrooms should be secure 81 Holding, Ordering, and Setup Costs Holding costs - holding cost is money spent to keep and maintain a stock of goods in storage (rent, space, insurance and security) Ordering costs - the costs of placing an order and receiving goods Setup costs - cost to prepare a machine or process for manufacturing an order 82 Cycle Counting Items are counted and records updated on a periodic basis Often used with ABC analysis to determine cycle Has several advantages Eliminates shutdowns and interruptions Eliminates annual inventory adjustment Trained personnel audit inventory accuracy Allows causes of errors to be identified and corrected Maintains accurate inventory records 83 Independent Versus Dependent Demand Independent demand - the demand for item is independent of the demand for any other item in inventory Dependent demand - the demand for item is dependent upon the demand for some other item in the inventory 84 Inventory Models for Independent Demand Basic economic order quantity Production order quantity Quantity discount model 85 Basic EOQ Model Economic order quantity is the level of inventory that minimizes the total inventory holding costs and ordering costs. Assumptions : The ordering cost is constant. The rate of demand is constant The lead time is fixed The purchase price of the item is constant i.e no discount is available The replenishment is made instantaneously, the whole batch is delivered at once. 86 Reorder Points Inventory level of an item which signals the need for placement of a replenishment order., taking into account the consumption of the item during order lead time and the quantitu required for safety stock. 87 Production Order Quantity Model Used when units are produced and sold simultaneously 88 Inventory level Production Order Quantity Model Part of inventory cycle during which production (and usage) is taking place Demand part of cycle with no production Maximum inventory t Time 89 Quantity Discount Models Reduced prices are often available when larger quantities are purchased TC = D Q S+ H + PD Q 2 90 Safety Stock Use safety stock to achieve a desired service level and avoid stockouts ROP = d x L + ss 91 Chapter 13 – Aggregate Planning 92 Aggregate Planning Aggregate planning is an operational activity which does an aggregate plan for the productions process, in advance of 2 to 18 months, to give an idea to management as to what quantity of materials and other resources are to be procured and when. when 93 Aggregate Planning Aggregate planning has certain prerequisite inputs which are inevitable. They include: Information about the resources and the facilities available. Demans forecast for the period for which the planning has to be done. Cost of various alternatives and resources. This includes cost of holding inventory, ordering cost, cost of production through various production alternatives 94 The Planning Process Long-range plans (over one year) Research and Development New product plans Capital investments Facility location/expansion Top executives Operations managers Intermediate-range plans (3 to 18 months) Sales planning Production planning and budgeting Setting employment, inventory, subcontracting levels Analyzing operating plans Short-range plans (up to 3 months) Operations managers, supervisors, foremen Responsibility Job assignments Ordering Job scheduling Dispatching Overtime Part-time help Planning tasks and horizon 95 Aggregate Planning Strategies 1. Use inventories to absorb changes in demand 2. Accommodate changes by varying workforce size 3. Use part-timers, overtime, or idle time to absorb changes 4. Use subcontractors 5. Change prices or other factors to influence demand 96 Aggregate Planning Options Option Advantages Disadvantages Changing inventory levels Changes in human resources. Inventory holding cost may increase. Shortages may result in lost sales. Varying workforce size by hiring or layoffs Avoids the costs of other alternatives. Hiring, layoff, and training costs may be significant. 97 Aggregate Planning Options Option Advantages Disadvantages Varying production rates through overtime or idle time Matches seasonal fluctuations without hiring/ training costs. Overtime premiums; tired workers; may not meet demand. Sub-contracting Permits flexibility and smoothing of the firm’s output. Loss of quality control; reduced profits; loss of future business. 98 Aggregate Planning Options Option Advantages Disadvantages Using partIs less costly and more time workers flexible than full-time workers. High turnover/ training costs; quality suffers; scheduling difficult. Influencing demand Uncertainty in demand. Hard to match demand to supply exactly. Tries to use excess capacity. Discounts draw new customers. 99 Aggregate Planning Options Option Back ordering during highdemand periods Advantages May avoid overtime. Keeps capacity constant. Disadvantages Customer must be willing to wait, but goodwill is lost. 100 Summary of Aggregate Planning Methods Techniques Graphical methods Transportation method of linear programming Solution Approaches Important Aspects Trial and error Simple to understand and easy to use. Many solutions; one chosen may not be optimal. Optimization LP software available; permits sensitivity analysis and new constraints; linear functions may not be realistic. 101 Summary of Aggregate Planning Methods Techniques Simulation Solution Approaches Change parameters Important Aspects Complex; may be difficult to build and for managers to understand. 102 Yield Management Yield management, also known as revenue management, is the process of understanding, anticipating and influencing consumer behavior in order to maximize revenue or profits (such as airline seats or hotel room reservations) The challenge is to sell the right resources to the right customer at the right time for the right price. 103 Yield Management Matrix Predictable Unpredictable Duration of use Price Tend to be fixed Tend to be variable Quadrant 1: Quadrant 2: Movies Stadiums/arenas Convention centers Hotel meeting space Hotels Airlines Rental cars Cruise lines Quadrant 3: Quadrant 4: Restaurants Golf courses Internet service providers Continuing care hospitals 104 Chapter 14 – Material Requirements Planning (MRP) and ERP 105 MRP Material Requirements Planning (MRP) is a software based production planning and inventory control system used to manage manufacturing processes. Benefits 1. Better response to customer orders 2. Faster response to market changes 3. Improved utilization of facilities and labor 4. Reduced inventory levels 106 An MRP system is intended to simultaneously meet three objectives: Ensure material and products are available for productions and delivery to customers. Maintain the lowest possible level of inventory. Plan manufacturing activities and purchasing activities. 107 Dependent Demand The demand for one item is related to the demand for another item In general, used whenever a schedule can be established for an item MRP is the common technique 108 Dependent Demand Effective use of dependent demand inventory models requires the following 1. 2. 3. 4. 5. Master production schedule Specifications or bill of material Inventory availability Purchase orders outstanding Lead times 109 Master Production Schedule (MPS) A Master Production Schedule (MPS) is a plan for production, staffing, inventory, etc Specifies what is to be made and when Inputs from financial plans, customer demand, engineering, supplier performance It helps to forecast demand, production costs, inventory costs, lead time, The MPS is the result of the production planning process 110 Master Production Schedule (MPS) 111 The Planning Process Production Capacity Inventory Marketing Customer demand Procurement Supplier performance Management Return on investment Capital Finance Cash flow Human resources Manpower planning Aggregate production plan Master production schedule Engineering Design completion Change production plan? Figure 14.1 112 The Planning Process Master production schedule Change requirements? Change master production schedule? Material requirements plan Change capacity? Capacity requirements plan No Realistic? Yes Is capacity plan being met? Is execution meeting the plan? Execute capacity plans Execute material plans 113 Focus for Different Process Strategies Make to Order (Process Focus) Number of end items Assemble to Order or Forecast (Repetitive) Stock to Forecast (Product Focus) Schedule finished product Typical focus of the master production schedule Schedule modules Schedule orders Number of inputs Examples: Print shop Machine shop Fine-dining restaurant Motorcycles Autos, TVs Fast-food restaurant Steel, Beer, Bread Lightbulbs Paper 114 Master Production Schedule (MPS) Can be expressed in any of the following terms: A customer order in a job shop (maketo-order) company Modules in a repetitive (assemble-toorder or forecast) company An end item in a continuous (stock-toforecast) company 115 Bills of Material List of components, ingredients, and materials needed to make product Provides product structure Items above given level are called parents Items below given level are called children 116 Bills of Material Modular Bills Modules are not final products but components that can be assembled into multiple end items Can significantly simplify planning and scheduling 117 Accurate Records Accurate inventory records are absolutely required for MRP (or any dependent demand system) to operate correctly Generally MRP systems require 99% accuracy Outstanding purchase orders must accurately reflect quantities and scheduled receipts 118 Lead Times The time required to purchase, produce, or assemble an item For production – the sum of the order, wait, move, setup, store, and run times For purchased items – the time between the recognition of a need and the availability of the item for production 119 ERP Enterprise resource planning (ERP) is a companywide computer software system used to manage and coordinate all the resources, information, and functions of a business from shared data stores. 120